It appears you're receiving the * because you're using week where some cross months. The * is basically saying there is more than one value available and it can only show one in that field.
One solution is to create a Viz in the Tooltip. See the attached. I changed the chart to a dual axis then added a table for both current and prior. Then I added the corresponding worksheet to the Tooltip in each measure. This way the table will show multiple values. You can reformat as you like.
I hope this helps.